Sony AVD-K150B Service Manual page 26

AVD-K150B/K150E/K150G/K150N/K150R
3. Y/C CIRCUIT
(4) When the Video signal doesn't appear on the screen in REC Mode,
Is the EE signal normal?
YES
Is 5.2VT/5.3VA applied to the
IC301 Pins24,42,55,72,91?
YES
Does PB Mdoe operate
normally?
YES
Does the RF signal appear
at the IC301 Pin78?
YES
Does the REC RF signal
appear at the IC301
Pins88,89,94,95?
YES
Check the Drum &
Drum Connector
26
NO
Check EE Mode.
NO
Check the line of the 5.2VT/
5.3VA Line.(Power Circuit)
NO
Check PB Mode.
Is the REC 'H' signal
NO
(about 4V) applied to the
IC301 Pin80?
YES
Check REC Luminance
Pass & Color Pass.
NO
Check the circuit of the
IC301 Pins85, 86.
Check the System of REC
NO
'H'. (the IC501 Pin47
/ the D301)
YES
Replace the IC301.
YES